The invention relates to a grain lifter for combine harvester mowing systems. The grain lifter has mowing fingers attached to a finger bar. The mowing fingers comprise a carrier rail connectable to the finger bar; a stem lifter connected to the carrier rail; and a fixing element connected to the carrier rail and securable to the finger bar. A holding element is attached to the carrier rail. The holding element includes two spaced arms which receive the tip of the mowing finger. Also, a holding means contacts an upper face of the mowing finger for supporting purposes.
In mowing systems, mowing fingers are arranged so as to be distributed along the finger bar. The fingers are bolted to the finger bar. The mowing fingers guide the cutter bar. The mowing fingers serve as a counter blade for the blades of the mowing knifes attached to the cutter bar. The blades, move to and fro.
Grain lifters are used to safely mow bent or lying crops. The grain lifters lift the stem material. Depending on the type and condition of the stem material and on the required cutting height, different settings are required for the mowing system. As a result, the alignment of the grain lifter relative to the ground also changes. However, the goal is to achieve an alignment which enables the sliding range of the grain lifter to be guided as parallel as possible relative to the ground. In practice, this is achieved by using grain lifters which enable a change in the orientation of their region projecting beyond the mowing finger tip. For this purpose, this region is raised or lowered to a greater or lesser extent relative to the mowing finger.
In this context, GB-A-2028088 illustrates the carrier rail of the grain lifter with a holding element. The holding element has two parallel arms between which the tip of the mowing finger can be inserted. The two arms each include pairs of bores arranged at different levels. A locking bar or locking pin supported on the upper face of the mowing finger can be guided through the bores associated with a pair of bores. Depending on the required orientation, one of the pairs of bores can be selected. This type of connection requires a certain amount of handling skill. It is disadvantageous because the locking bars can be lost in operation. Also, the bars can be lost after they have been released. To prevent loss, various means have been provided in the art to safely secure the locking bar at the holding element.
It is the object of the invention to provide a simplified grain lifter. In accordance with the invention, the holding means includes a two-arm locking lever. A first lever arm has a supporting face supported on the upper face of the mowing finger. The second lever arm has at least one engaging face. The two-arm locking lever is supported so as to be pivotable around a pivot pin between the two arms. A fixing element has a locking element which can contact one of the engaging faces of the second lever arm. Thus, the fixing element holds the locking lever in its position.
An advantage of this design is that, when aligning the grain lifter, starting from the released position, the mowing finger tip hits one of the lever arms and thus causes the locking lever to pivot towards the locked position. In order to transfer the locking lever into the required position, one hand is used to raise the grain lifter region projecting beyond the mowing finger tip. The other hand is used to apply pressure to the second arm of the locking lever, to bring the locking lever into contact with the locking element. Accordingly, no components can be lost. Furthermore, it is not necessary to find the right position to guide the locking bar through the bores of the pair of bores, as is needed in the prior art.
It is possible to provide any number of engaging faces, but three engaging faces are sufficient. These are preferably provided in the form of parts of engaging teeth. In one advantageous embodiment, the locking element is formed by a leaf spring. The spring resiliently establishes contact in the direction towards the engaging faces of the locking lever. The respective engaging positions are then assumed automatically without the need for a manual locking operation. For engaging purposes, the leaf spring has an end face which establishes contact with one of the engaging faces. For example, this can be the free end of the leaf spring which is otherwise locally fixed. Also, it is possible to select an orientation which ensures that if pressure is applied, there is no risk that the leaf spring will escape. However, according to a further embodiment, the leaf spring has an aperture. One of the faces of the aperture is designed as a contact face. The locking lever, via its engaging face, establishes contact with the contact face. Also, it is possible to provide an arrangement whereby the leaf spring, in the engaged condition, is subjected to tension.
A particularly advantageous embodiment is achieved if the first and the second lever arm adjoin one another at an angle and if the pivot axis of the pivot pin is arranged in the region of the abutment. For this purpose, the locking lever is preferably provided with a bore. The locking lever is received on the pivot pin in the bore. The position of the fixing element can be chosen such that, during mounting, the second lever arm is displaced by the mowing finger into its first engaging position. Accordingly, one of the engaging faces enters into an operating connection with the locking element. To release the locking element, the locking lever has to be moved out of the operating connection with the locking element. In the embodiment where the locking element is in the form of a leaf spring, it is possible to use a screwdriver.
While it is possible for the arms of the fixing element to be integral with the carrier rail, it is preferred to connect the arms to one another by a web and to secure the web to the carrier rail. This results in a U-shaped form of the holding element. Alternatively, the arms can be connected to one another by two separate webs. The webs are secured to the carrier rail. The height of the arms is such that the first lever arm projects upwardly beyond the arms to be able to act from the outside on the first lever arm. According to a further embodiment, the leaf spring is arranged so as to be protected between the arms in the range of movement of the second lever arm.
For an alternative type of engagement, the locking lever in the region of its second lever arm is provided with an oblong hole which is passed by a pivot pin. The locking element is in the form of a stop fixed in position. For releasing purposes, the locking lever can be pulled out of contact with the stop. The return into the engaged position can be effected by hand. However, it is also possible to load the locking lever by a spring force into a position where the stop is positioned within the range of movement of the second lever arm. As far as the design of the holding element is concerned, the two arms of the holding element are connected to one another by a web. This achieves a substantially U-shape embodiment. The stop is preferably connected to the web or it forms part of the web. Here, the locking lever is arranged between the two arms. The stop can be formed by a bent part of the web.
To provide the spring force, a pressure spring is received in the oblong hole of the second lever arm of the locking lever. The spring is supported between an end face of the oblong hole and the pivot pin. To facilitate the release of the locking lever from the engaged position, its first lever arm has an aperture. A piece of wire or tool is guided through the hole to facilitate the displacement of the locking lever into the released position. A pressure spring is not required to achieve the locking effect. However, the spring force facilitates the re-setting of the locking lever into a position where its second lever arm, by means of its engaging faces, can be moved into contact with the stop. The locking lever itself is held in the locked position via the resilient pre-tension of the carrier rail. The carrier rail, at one end, is secured to the finger bar. The end of the carrier bar is yoke-shaped and, via a recess, is insertable into a groove of a pin. An oblong hole is provided in the locking lever to provide a region of engagement to receive the pivot pin to additionally secure the locking lever against displacement.
From the following detailed description, taken in conjunction with the drawings and subjoined claims, other objects and advantages of the present invention will become apparent to those skilled in the art.